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From: richard clark <richard.xnu.clark@gmail.com>
Date: Mon, 5 Feb 2024 17:57:29 +0800
Message-ID: <CAJNi4rMpt88Gz+149wR9crzApmfUEfpS05sbOgAvOhzh2+Brbg@mail.gmail.com>
Subject: Question about the ipi_raise filter usage and output
To: nico@fluxnic.net, Steven Rostedt <rostedt@goodmis.org>, 
	Mark Rutland <mark.rutland@arm.com>, mhiramat@kernel.org
Cc: linux-arm-kernel@lists.infradead.org, linux-trace-kernel@vger.kernel.org, 
	linux-kernel@vger.kernel.org, richard clark <richard.xnu.clark@gmail.com>
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Hi guys,

With the ipi_raise event enabled and filtered with:
echo 'reason == "Function call interrupts"' > filter, then the 'cat
trace' output below messages:
..
insmod-3355    [010] ....1.. 24479.230381: ipi_raise:
target_mask=00000000,00000bff (Function call interrupts)
..
The above output is triggered by my kernel module where it will smp
cross call a remote function from cpu#10 to cpu#11, for the
'target_mask' value, what does the '00000000,00000bff' mean?
 ~~~~~~~~~~~~~~

Another question is for the filter, I'd like to catch the IPI only
happening on cpu#11 *AND* a remote function call, so how to write the
'target_cpus' in the filter expression?

I try to write below:
echo 'target_cpus == 11 && reason == "Function call interrupts"' >
events/ipi/ipi_raise/filter

But the 'cat trace' doesn't show anything about cpu#11 IPI info,
although both the /proc/interrupts and the smp_processor_id() in the
remote function shows there's IPI sent to the cpu#11.

Any suggestions?

Thank you!